By Ron Cowen
The cosmic backyard will never look the same, thanks to a new three-dimensional map — the most detailed view ever assembled out to a distance of 380 million light-years.
Covering 95 percent of the sky, the map uses dust-penetrating infrared observations to reveal features that in visible light are obscured by the Milky Way. “We get a more detailed look at major structures that are almost hidden by our galaxy, like the Hydra-Centaurus supercluster and the Norma supercluster of galaxies,” said Karen Masters of the University of Portsmouth in England. She unveiled the map, which catalogs some 45,000 galaxies, on May 25 at a meeting in Boston of the American Astronomical Society.
Because the map encompasses nearly the entire sky rather than the smaller wedges revealed by previous surveys, it shows in new detail how clusters of galaxies congregate into vast walls and filaments, said Michael Hudson of the University of Waterloo in Canada. Hudson’s team has already used the data to find that a vast concentration of galaxies called the Shapley concentration is about twice as massive as previously estimated.